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9 votes
9 votes
At noon Joyce drove to the lake at 30 miles per hour. but she made the long walk back home at 4 miles per hour. How long did she walk if she was gone for 17 hours? How far did she walk?

PLEASE GIVE A REAL ANSWER , WILL GIVE BRANILIEST

User Rishikesh Raje
by
3.0k points

2 Answers

21 votes
21 votes

Distance be x

  • Time=Distance/Speef

So

  • T_1=x/30
  • T_2=x/4

ATQ


\\ \tt\hookrightarrow T_1+T_2=17


\\ \tt\hookrightarrow x/30+x/4=17


\\ \tt\hookrightarrow 2x+15x/60=17


\\ \tt\hookrightarrow 17x=1020


\\ \tt\hookrightarrow x=60mi

User Kelly Bang
by
3.2k points
11 votes
11 votes

Answer:

60 miles

Explanation:

let d = distance to the lake

Using: time = distance ÷ speed

Create expressions for the time it takes for each journey:

Drive:
t_1=(d)/(30)

Walk:
t_2=(d)/(4)

If total time = 17 hours


\implies t_1+t_2=17


\implies (d)/(30)+(d)/(4)=17


\implies (17d)/(60)=17


\implies 17d=1020


\implies d=(1020)/(17)


\implies d=60

Therefore she walked 60 miles

User Svetlozar
by
3.3k points